1. Field of the Invention
The present invention relates to a vehicle control apparatus, and more particularly to a control apparatus which calculates a final vehicle control value based on a basic value and a correction value varying with operating conditions of a vehicle.
2. Description of Related Art
An internal combustion engine for vehicles, for instance, is controlled by an electronically-controlled fuel injection apparatus. This apparatus calculates a basic fuel injection value (fuel injection duration) Tp based on the detection values of an engine rotation speed and an intake air pressure (intake air quantity), and various correction values based on engine operating conditions and various mechanical characteristics of the engine. The apparatus calculates a final injection value (duration) TAU based on the calculated basic value and correction values to drive fuel injectors for the final value TAU for fuel injection.
More specifically, the apparatus executes various calculations in the order shown in FIG. 17 to calculate the final injection value TAU from the basic value TP and the following exemplary correction values.
FTHW: warm-up fuel enrichment correction for increasing fuel for engine warm-up in accordance with engine coolant temperature;
FASE: after-start fuel enrichment correction for increasing fuel after engine starting;
FKL: small air enrichment correction for increasing fuel in case of small intake air quantity;
RICHX: enrichment correction for increasing fuel in accordance with a maximum of radiator temperature RAD, catalyst over-temperature OT and the like;
IDL: idling correction for increasing and decreasing fuel to prevent engine stall at the time of engine idling;
AF: air-fuel ratio correction for increasing and decreasing fuel to maintain the air-fuel ratio of air-fuel mixture;
FMW: wall-sticking fuel correction to increase fuel amount in correspondence with sticking of injected fuel around an engine intake valve; and
ADJ: adjustment correction for increasing and decreasing fuel from an external side.
The above calculation processing must be changed from engine to engine and vehicle to vehicle, because the characteristics of engines and vehicles are different from each other. For instance, additional correction values may have to be calculated in some types of engines, and some of the above correction values may have to be omitted in other types of engines.
It is thus required to check a control program of the control apparatus and modify the same, each time the type or specification of the engine or vehicle is changed. This program check and modification requires an enormous program development or modification workload, because it is very difficult to find out the sections in the program to be modified. Thus, it is almost impossible to use the program for one apparatus to another apparatus.